Modulating the Electronic Structure of Co₂P/NiWO₄ by Interfacial Engineering for Enhanced Seawater Electrolysis

Seawater electrolysis for both hydrogen and oxygen production is of great significance, yet the development of highly active and stable bifunctional catalysts remains a great challenge. Herein, we employ the interfacial engineering strategy to tune and optimize hierarchical Co2P/NiWO4 toward efficient and stable bifunctional electrocatalysts for seawater splitting. Benefiting from high electrical conductivity, large surface area, and abundant active sites, this resultant catalyst displays a high catalytic performance toward the hydrogen and oxygen evolution reaction (HER/OER), affording low overpotentials of 44 and 230 mV at 10 mA cm–2, respectively. Besides, the hierarchical structure leads to higher stability and corrosion resistance, which helps the Co2P/NiWO4 electrocatalyst work well under harsh conditions in seawater. As a result, the Co2P/NiWO4 electrode can afford current densities of 10 and 100 mA cm–2 at voltages of 1.59 and 1.76 V in seawater, respectively, with stability over 100 h of continuous testing. This work provides a versatile interface engineering strategy to synthesize high-performance electrocatalysts for hydrogen generation from seawater splitting.